The major feature of the proposed work is to extend the characterization of those new compounds which we have prepared which are effective antidotes for methyl mercury poisoning. We have prepared about 20 new water soluble chalating agents and about 5 new chalating polymers, most of whose structures are designed to function as selective chelating agents for mercury. Of these, the polymer formed between terephthaldehyde and mercaptoethyl sulfide has shown itself to be an effective antidote for methyl mercury poisoning and also in reducing the body burden of radioactive mercury in mice given less than toxic amounts. The polymer is administered orally as an addition to the food of the animals (1%). We plan to extend this work to two other species of animals and to carry out detailed studies of organ histopathology on the animals. The synthesis of new chelating agents will concentrate on the search for new arrangements of S and N donor groups in simple and polymeric chelating agents which possess a special selectivity for Hg ions. In the immediate future we also plan to prepare simple water-soluble compounds containing the -C(SH)-C(SH)-grouping polymers containing this grouping and the calcium complex of -(CH2 CH(NHCH2COOH)-n for further testing. This latter polymer seems capable of offsetting the initial effects of methyl mercury poisoning, but its long term use ultimately deranges essential metal ion equilibria (like FDTA). The calicum complex will be used in an attempt to obviate this. BIBLIOGRAPHIC REFERENCES: Mark M. Jones, Thomas H. Pratt, Wanda G. Mitchell, Raymond D. Harbison, and James S. MacDonald, Journal of Inorganic and Nuclear Chemistry 38, 613-616 (1976). "Enterohepatic Chelating Agents - I. General Principles and Examples".